Electromagnetic relay



June 7, 1966 H. A. KRASUN 3,255,323

ELECTROMAGNETI C RELAY Filed 001:. 14, 1964 2 Sheets-Sheet 1 I nvenlorHENR Yk A. ASU/V By m 4%? A Home y June 7, 1966 H. A. KRASUN 3,255,323

ELECTROMAGNETIC RELAY Filed Oct. 14, 1964 2 Sheets-Sheet 3 InventorHNRYK A. kkASU/V Attorney United States Patent 3,255,328 ELECTROMAGNETICRELAY Henryk Adam Krasun, London, England, assignor to InternationalStandard Electric Corporation, New York, N.Y., a corporation of DelawareFiled Oct. 14, 1964, Ser. No. 403,742 Claims priority, application GreatBritain, Oct. 22, 1963, 41,646/ 63 2 Claims. (Cl. 200-87) This inventionrelates to an electromagnetic relay, and especially to such a relay forhandling a fairly high current.

According to the present invention there is provided an electromagneticrelay in which the magnetic circuit consists of a generally rectangularframe on one limb of which a winding is mounted, the limb of said framewhich is generally parallel with the limb which carries the windingacting as an armature, in which said armature is pivotally attached toone of the other two limbs of the frame, the limb parallel to the one towhich the armature is-pivoted acting as a front stop for said armature,and in which said armature has an extension piece for contact operation.

An embodiment of the invention will now be described with reference tothe accompanying drawings, in which:

FIG. 1 is a cross-section of a relay according to the invention;

FIG. 2 is a plan view of the relay, seen with its top cover removed;

FIGS. 3 and 4 are side and plan views respectively of the armature ofthe relay;

FIG. 5 is a view from the left-hand end (as seen in FIG. 1) of therelay; and

FIG. 6 shows the yoke plus coil separate.

The relay is a relatively cheap and easily produced arrangement intendedto control a single pair of contacts capable of handling up to amperes,and is especially intended for use in domestic electrical apparatus. Itis enclosed in a generally rectangular container of a suitableinsulating material such as nylon or some other suitable material, thematerial used being preferably one capable of accepting a good finish.The container consists of a generally U-shaped portion 1, which consistsof the ends and the top of the container. When assembly is completed thesides and if necessary the bottom are closed by further plates ofinsulating material. The two end portions have various holes whose useswill become apparent in due course, and also have their inner surfacesformed to receive the magnetic circuit. Thus there are recessesindicated at 2, 3, FIG. 2 into which the magnetic circuit is fitted.These locate the yoke and coil within the container.

The magnetic circuit, which is generally rectangular, consists of aC-shaped (or U-shaped) portion 4, FIG. 6, with a hole 5 at one end, thecorner of this end being rounded off as seen in FIG. 6. The other end isbevelled, also as shown in FIG. 6. Moulded on to, the horizontal limb ofthe yoke, as seen in FIG. 6, is a coil former and cheeks 6, 7, asuitable material for this being a plastics material, such as that knownas Delrin. This carries the winding 8, which in the example shown is ahigh resistance multi-turn winding.

The armature 11, see FIGS. 3 and 4, is a straight member having smallwings 12, 13 which when installed are one on each side of the yoke andthus improve the magnetic circuit. The armature has twodownwardly-extending lugs 15, 16 which close the magnetic circuit, thesebeing cut atan angle as shown to cooperate with the sloping end of theyoke pole-piece. This reduces the air gap in the magnetic circuit whenthe coil is deenergised and the magnetic circuit opened.

3,255,328 Patented June 7, 1966 ice The armature also has a bent end 14which is the contact operating portion. The end 14 is working on alonger radius than the pole-pieces on the armature and yoke, whichenables the magnetic air gap to be smaller than the gap of theelectrical contacts. This reduces the power needed to operate the relay.

The yoke and coils which form a subassembly, are inserted from thebottom and the armature is inserted into the container from theright-hand end, FIG. 1, and both are secured to the yoke by a pin goingthrough holes in wings 12, 13 and the hole 5 in the yoke. The ends ofthe winding are then connected to terminal taps such as 9, FIG. 1.

The contact springs 17, 18 are, as shown in FIG. 2, each of L-form andare of Phosphor bronze or beryllium copper, with a contact button oneach. These are inserted into the container from the left to theposition shown in FIG. 1, and then fixed by a screw or moulded in place.The resilience of the uppermost spring 15 urges the armature away fromthe yoke and provides the returning force needed to release the relaywhen its coil is deenergised.

After assembly the various elements are moulded in place by a suitablemoulding compound, and the sides and if desired the bottom, closed byplates.

It is understood that the foregoing description of specific examples ofthis invention is made by way of example only and is not to beconsidered as a limitation on its scope.

What I claim is:

1. An electromagnetic relay having a magnetic circuit comprising:

a U-shaped frame having a base limb and two limbs of diiferent lengthsextending in parallel from the ends thereof and perpendicular to saidbase limb;

an energizing winding carried on said base limb forming a coil of themagnetic circuit thereat;

a pair of contact members mounted parallel to said base limb, with saidtwo perpendicular limbs extending therebetween, said pair of contactmembers having means at the ends thereof for electrical contacttherebetween, said contact members being resilient to normally urge saidcontact members apart;

an armature, pivotally joined to the longer one of said two limbs, andpositioned parallel to said base limb with said pair of contact memberstherebetween, said armature having a pair of lugs intermediate the endsthereof, said lugs being directed toward the shorter of said two limbsto provide a magnetic circuit air gap between said pair of lugs and saidshorter limb, and a bent portion opposite the pivoted end of saidarmature, and said bent portion contacting the upper one of saidresilient contact member to urge said upper contact member into contactwith the other contact member when said magnetic circuit is energized.

2. A relay as claimed in claim 1, and in which each said contact memberis of generally L-shape, with the bases of the L-shaped portionsextending towards each other in overlapping relation.

References Cited by the Examiner UNITED STATES PATENTS 6/1934Morgenstern ZOO-104.1

2/1958 Grissinger et a1. ZOO-109.1

1. AN ELECTROMAGNETIC RELAY HAVING A MAGNETIC CIRCUIT COMPRISING: AU-SHAPED FRAME HAVING A BASE LIMB AND TWO LIMBS OF DIFFERENT LENGTHSEXTENDING IN PARALLEL FROM THE ENDS THEREOF AND PERPENDICULAR TO SAIDBASE LIMB; AN ENERGIZING WINDING CARRIED ON SAID BASE LIMB FORMING ACOIL OF THE MAGNETIC CIRCUIT THEREAT; A PAIR OF CONTACT MEMBERS MOUNTEDPARALLE TO SAID BASE LIMB, WITH SAID TWO PERPENDICULAR LIMBS EXTENDINGTHEREBETWEEN, SAID PAIR OF CONTACT MEMBERS HAVING MEANS AT THE ENDSTHEREOF FOR ELECTRICAL CONTACT THEREBETWEEN, SAID CONTACT MEMBERS BEINGRESILIENT TO NORMALLY URGE SAID CONTACT MEMBERS APART; AN ARMATURE,PIVOTALLY JOINED TO THE LONGER ONE OF SAID TWO LIMBS, AND POSITIONEDPARALLEL TO SAID BASE LIMB WITH SAID PAIR OF CONTACT MEMBERSTHEREBETWEEN, SAID ARMATURE HAVING A PAIR OF LUGS INTERMEDIATE THE ENDSTHEREOF, SAID LUGS BEING DIRECTED TOWARD THE SHORTER OF SAID TWO LIMBSTO PROVIDE A MAGNETIC CIRCUIT AIR GAP BETWEEN SAID PAIR OF LUGS AND SAIDSHORTER LIMB, AND A BENT PORTION OPPOSITE THE PIVOTED END OF SAIDARMATURE, AND SAID BENT PORTION CONTACTING THE UPPER ONE OF SAIDRESILIENT CONTACT MEMBER TO URGE SAID UPPER CONTACT MEMBER INTO CONTACTWITH THE OTHER CONTACT MEMBER WHEN SAID MAGNETIC CIRCUIT IS ENERGIZED.